systems grow from small-scale applications into
industry-wide systems, the IT manager must be in a
position to make the difficult choice about when to
migrate from Intel-based MS Windows architecture to an
industrial-strength UNIX environment.
UNIX dominates the large-system market, while
Windows-based applications are established in the
small-size application tier. The confounding question is:
When is it appropriate for a company to undertake the
migration to UNIX?
Gartner Research published "Server Operating Systems—UNIX
vs. NT: Perspective" in January 2000. In this
comprehensive report, some conclusions were reached about
UNIX and MS Windows NT:
- UNIX has become the standard for building
large-scale application servers (Internet services,
database management), while NT is used primarily as a
departmental server (messaging, file/print).
- Though its implementation may prove expensive, UNIX
offers a higher degree of reliability and scalability
than NT. This is measured by time span between reboots
and percentage of uptime.
- Unlike UNIX, NT's file directory structure allows an
application config file to be placed almost anywhere,
which leads to problems, including having several
versions of a single DLL file on the same system with
the same filename.
- UNIX does not require administrators to reboot after
making minor configuration modifications. NT does.
- With UNIX, there is a built-in ability to manage the
on the move to UNIX
Many industry experts believe that the best way to gauge
the success of database architectures is to do a market
survey and choose architectures similar to those chosen by
successful shops. For example, as of 2001, more than 95
percent of all Oracle data was stored in a UNIX
"The NT market will grow faster than the UNIX market, but
there are still more dollars in the UNIX market, where
database management systems frequently sit on large
servers and work for more users," said Merv Adrian,
database analyst for the
Giga Information Group Inc.
Susan Frankle, director of server research at IDC, said,
"NT has made a significant impact on file server, print
server and basic Internet applications, but it won't be
all things to all people. Microsoft is very good at
providing productivity applications support, but it does
not really know how to support enterprise-wide networks
and the applications that run on them."
Frankle adds, "The Windows software isn't widely accepted
away from the Intel Corp. platform, and Microsoft lacks
value-added service and support for installations on an
Here are some other points by which to compare UNIX and
UNIX: UNIX supports a 64-bit architecture to allow
for very fast processing speeds for mission-critical
NT: Intel-based 64-bit processors are still
considered too unreliable for production systems.
UNIX: All systems require additional vendor tools
for backup, recovery, tape, and system management. The
vast majority of these tools are provided solely for UNIX
NT: Many hardware-level file management tools are
not available for NT, and failure to get into a UNIX
environment will severely limit the choices of systems
UNIX: The UNIX operating system has been around for
more than 20 years. During this time, UNIX has evolved
into a sophisticated environment that supports a huge
variety of systems with high reliability, excellent
security, and proven hardware-level backup and recovery
NT: Windows NT is less than 10 years old and has
been struggling with serious reliability, security, and
UNIX: UNIX servers have become extremely reliable
as evidenced by their widespread use in banking
applications. My clients with NT servers must reboot the
servers each week to clean up RAM memory leaks.
NT: NT's unreliability is demonstrated in the
system management tools. For example, NT Wolfpack cluster
technologies' sole purpose is to provide failover when an
NT server crashes and to attempt to provide high
availability. When a UNIX CPU fails, the OS often
continues processing without service interruption, and the
server telephones its vendor to report the problem.
UNIX: Sun and HP offer robust UNIX servers that
utilize sophisticated SMP subsystems to achieve high
performance and scalability. Large corporations that use
Oracle choose a UNIX vendor who offers servers that can
easily accept new RAM and CPU as demand increases.
NT: NT 3.1 through 4.0 Server supports up to four
processors. NT 4.0 Server Enterprise Edition supports up
to eight processors.
UNIX: Although attacks on UNIX and Linux have
become more frequent, the system has a solid history and
was designed and built around a secure environment. With
TCP wrappers, firewall capability, and the SOCKS library,
the UNIX platform can be hardened into a reliable source
NT: Windows NT servers are prone to attacks from
external hackers and viruses. In October of 2001, those
Oracle users unfortunate enough to use Oracle on NT
experienced a catastrophic loss of data with the NIMDA
virus. Gartner has predicted that by the end of 2006, 25
percent of large enterprises will carry hacker insurance.
Gartner believes that if Microsoft's security flaws are
not addressed, 75 percent of providers of computer
security insurance will apply surcharges to premiums for
NT users by the end of 2002.
Once the decision has been made, a migration to UNIX will
involve the following tasks. Each of these tasks is a
major IT decision and is normally made by a high-level IT
- Choosing a UNIX hardware vendor (Sun, HP):
Once chosen, the company must choose a SMP server
according to projected short-term processing demands and
choose a data server with fast scalability.
- Choosing the Network environment: The
appropriate choice of routers and network hardware must
me made to ensure adequate response time and eliminate
- Choosing a disk storage vendor: This step
involves choosing a disk vendor and an appropriate RAID
architecture for the data. To eliminate multivendor
issues, management may want to go with the same vendor
as the server (Sun, HP).
- Choosing a backup and recovery strategy: It
is highly recommended that companies choose
hardware-level Oracle backup and recovery, using one of
the major vendor products such as Veritas or EMC.
Companies will also need to choose a tape management
system, choosing between ADSM, Legato, or Veritas.
- Planning the migration: A downtime window
must be scheduled to allow the existing system to
migrate into the new architecture. A UNIX expert will be
contracted to install the Oracle server and ensure that
the IT staff (and the new UNIX systems administrator)
understand the installation.
- UNIX Training: All DBA and developers should
attend a five-day course in UNIX. This training should
be done immediately prior to the migration to minimize
loss of knowledge.